Black days
by Siriuslycouldn'tthinkofaname
Summary: Cassiopeia Black, illegitimate daughter of Sirius Black, enters Hogwarts at the same time as Harry Potter and friends. Mostly canon for Harry's storyline, though Cassie has different adventures that link closely to the canon plot. AU. No slash.
1. Chapter 1

**Disclaimer: I do not own HP and it's characters, they are all the work of Mrs J.K. Rowling.**

**Author's Note: Hi all! Thanks for looking at my story, I hope you enjoy reading it. The first couple of chapters follow the book extremely closely and only really start to move away from the books in chapter 3. If you can stick with it until then, I promise you it gets more interesting!**

Cassiopeia Black was, for the first time in her life, early. And it was boring. She and her Uncle had arrived early because his monster of a boss had demanded he come in. His boss was too much of a cow to give him the morning off to say goodbye before she left for boarding school. What this meant for Cassie was that while Platform 9 ¾ gradually filled with teary eyed parents, she was alone, in a compartment, heading off to a world where she knew very few people. She suspected that she wouldn't be welcomed warmly either. A ball of nerves settled in her stomach and seemed content to remain there. There were so many 'what ifs' swirling around her head she was almost ready to bash her skull on the window just for a moment of peace.

Sighing, she looked at her reflection in the pane of glass and felt a pang of sadness. Cassie was a lot like her father in looks, the tameable black hair and crystal blue eyes were characteristic of the house Black. She knew that once any pureblood or half-blood heard her name they would give her a wide berth. Nobody would want to be associated to the daughter of the traitor and murderer Sirius Black. Her Uncle didn't like to talk about him.

The Hogwarts Express gave a long whistle, a warning to the last students to board. A knock on the compartment door made her look over startled, a feeling of dread formed in the pit of her stomach. She spotted a mop of messy black hair and a pair of emerald green eyes hidden behind battered round glasses.

"Hello? I was wondering if I could sit here?" Harry Potter asked sheepishly dragging a trunk and owl cage behind him.

Cassie felt her mouth go dry so she just nodded.

He gave her a relieved smile before handing her the beautiful snowy owl's cage while he tried to wrestle his trunk onto the train.

"Want a hand?" A red haired boy asked.

Cassie hoped he wouldn't refuse, not liking the idea of having to help heave such a heavy trunk.

"Yes, please," Harry panted.

"Oy, Fred! C'mere and help!"

With the twins' help, Harry's trunk was at last tucked away in a corner of the compartment.

"Thanks," said Harry pushing his sweaty hair out of his eyes.

"What's that?" said one of the twins suddenly, pointing at Harry's lightning scar.

"Blimey," said the other twin. "Are you-?"

"He is," said the first twin. "Aren't you?" He added to Harry. Cassie rolled her eyes in amusement.

"What?" said Harry.

"_Harry Potter,"_ chorused the twins.

"Oh, him," said Harry and she couldn't fight the grin that crept onto her face. "I mean, yes, I am."

The two boys gawped at him.

"You'll catch flies with your mouths open like that," Cassie remarked, noticing Harry's face flush in embarrassment.

Her comment made them snap their jaws shut, just as a voice came floating in through the trains open door.

"Fred! George? Are you there?"

"Coming, mum."

With a last look at Harry, the twins hopped off the train. Harry took the other seat next to the window, where she could tell he was watching the family of redheads intently.

"We'll send you a toilet seat!"

"George!"

"Only joking, mum."

The train began to move. Houses flashed past the window. The door of the compartment slid open and a younger red headed boy came in.

"Anyone sitting here?" he asked, pointing at the space beside her. "Everywhere else is full."

Harry shook his head after a quick questioning glance at Cassie and the boy sat down.

Cassie pointedly ignored the boy who was quite obviously a Weasley, in hope that he would just forget she was there at all. She hoped they wouldn't ask for her name, as that would probably open up a whole bag of worms she didn't want opened yet. Thankfully, the twins reappeared again and soon the two boys found plenty to talk about. Ron easily forgot about her in favour of talking to Harry.

While they were talking, the train had carried them out of London. Now they were speeding past fields full of cows and sheep. They were quiet for a time, watching the fields and country lanes flicker past.

Around half past twelve there was a great clattering outside in the corridor and a smiling, dimpled woman slid back their door and said, "Anything off the trolley dears?"

Harry, who looked like he hadn't eaten in a week, leapt to his feet, but Ron mumbled something about sandwiches. Harry went out into the corridor.

Ron turned to Cassie, "Can you believe we're sitting with _Harry Potter?" _He whispered.

Cassie resisted the urge to roll her eyes at him. "Yeah it's pretty crazy," she agreed. Quickly she returned her attention to the window in the hope that he would stop talking to her. He didn't catch the hint.

"I thought he'd be really different, full of himself or something," Ron murmured as Harry handed over a small heap of coins to the trolley lady. "Hey!" he realised suddenly, "I never asked you your name? I'm Ronald Weasley, nice to meet you,"

Luckily Harry entered the compartment again, tipping what looked like the contents of the entire trolley onto an empty seat.

"Hungry, are you?" Ron asked.

"Starving," said Harry, taking a large bite out of a pumpkin pasty.

Ron took out a lumpy package and unwrapped it. There were four sandwiches in there. He pulled one of them apart and said, "She always forgets I don't like corned beef."

Cassie looked on in amusement but said nothing, she hadn't thought to pack anything to eat herself and her Uncle, who was always a little short on money meant she would have to wait until after the sorting ceremony to get her fill.

Perhaps then she would explore the castle, something she was eagerly anticipating.

Though, she thought as her stomach grumbled, it was a long time before they would reach Hogwarts. Her grumbling stomach caught Harry's attention and she smiled sheepishly at him.

He grinned as both her and Ron's eyes strayed to the pile of chocolate frogs waiting to be unwrapped.

"Help yourself," said Harry. "But in, you know the muggle world, people just stay put in photos." He said in answer to whatever they were on about.

The countryside now flying past the window was becoming wilder. The neat fields had gone. Now there were woods, twisting rivers and dark green hills.

There was a knock on the door of their compartment and a round faced boy came in. He looked tearful.

"Sorry," he said, "but have you seen a toad at all?"

When they shook their heads, he wailed, "I've lost him! He keeps getting away from me!"

"He'll turn up," said Harry.

"Yes," said the boy miserably. "Well, if you see him…"

He left.

"Don't know why he's so bothered," said Ron. "If I'd brought a toad I'd lose it as quick as I could. Mind you, I brought Scabbers, so I can't talk."

The rat was still snoozing on Ron's lap when they were interrupted again, just as he was lifting his wand to perform a spell. The toadless boy was back, but this time he had a girl with him. She was already wearing her new Hogwarts robes.

"Has anyone seen a toad? Neville's lost one," she said. She had a bossy sort of voice, lot's of bushy hair and rather large front teeth.

"We've already told him we haven't seen it," said Ron, but the girl wasn't listening, she was looking at the wand in his hand.

"Oh, are you doing magic? Let's see it, then."

She sat down. Ron looked taken aback.

"Er-all right."

He cleared his throat.

"Sunshine, daisies, butter mellow, turn this stupid, fat rat yellow."

He waved his wand, but nothing happened. Scabbers stayed grey and fast asleep. Cassie could tell that his twin brothers must have had a hand in this little prank. She almost felt bad that Ron had fallen for such an obvious trick and she had to hold in her laugh.

"Are you sure that's a real spell?" said the girl and Cassie could hear a distinct 'Remus' quality that made her want to laugh some more. "Well, it's not very good is it? I've tried a few simple spells just for practise and it's all worked for me. Nobody in my family's magic at all, it was ever such a surprise when I got my letter, but I was ever so pleased, of course, I mean, it's the very best school of witchcraft there is, I've heard- I've learnt all of our set books off by heart, of course, I just hope it will be enough- I'm Hermione Granger by the way, who are you?"

She said all this very fast.

"I'm Ron Weasley," Ron muttered.

"Harry Potter," said Harry.

"Are you really?" said Hermione. "I know all about you of course, I got a few extra books for background reading, and you're in _Modern Magical History_ and _The Rise and Fall of the Dark Arts_ and _Great Wizarding Events of the Twentieth Century_."

"Am I?" said Harry, looking dazed.

"Goodness, didn't you know, I'd have found out everything I could if it was me," said Hermione. "Do any of you know what house you'll be in? I've been asking around and I hope I'm in Gryffindor, I hear Dumbledore himself was one, but I suppose Ravenclaw wouldn't be too bad… Anyway, we'd better go and look for Neville's toad. You had better change, you know, I expect we'll be there soon."

And she left taking the toadless boy with her. Cassie stood up as well, grabbing her robes to change into and taking off after Hermione and Neville.

"Hey, wait! I'll help you look for that toad." She called out hopefully, to be rewarded with two happy grins.

Hermione looked embarrassed. "I'm so sorry, I didn't even get your name in there. You know, I just get so nervous talking to new people, my brain just lets loose all of the things I've learnt and… Gosh! It's just unbelievable to think about magic when just under a year ago I was looking at normal secondary schools to go to and now, well now I carry a wand!"

Cassie grinned at Hermione's enthusiasm. "I'm Cassiopeia Black, but just call me Cassie." Hermione beamed back at her. She seemed to be thinking very hard. Neville Longbottom also looked very thoughtful.

Hopefully Hermione hadn't looked too closely at her family tree. She probably wouldn't react so well to her otherwise. Neville looked a lot more cautious, his face turning white as he shook her hand and stammered out his name.

They carried on a little way down the train until they came to Neville and Hermione's compartment.

"You can get changed in here," Hermione offered and Cassie did.

They stood around and chatted politely for a while when there was a commotion down the corridor, coming from Harry and Ron's compartment. Out of which three boys tumbled out and roughly pushed past them in their haste to leave.

Hermione tutted, "I'd best go and see if they've gotten changed yet, they seemed a bit hopeless earlier. Oh, I do hope they haven't been fighting, it would be awful for them to get a detention before they've even begun yet."

Cassie couldn't help but disagree, the first detention of the year was a great honour. She figured this may have been her Uncle's fault as he told her about the Marauder's exploits, a group of legendary boys that went to school at the same time as him.

Hermione trotted off back down the train, leaving her and Neville with an awkward silence.

"So," Neville started nervously. "You're a Black?" Cassie felt a flicker of anger at the name.

She scowled. "In blood and name only, I wish I could change it to my mum's maiden name and be done with the whole family."

Neville looked slightly relieved by this news. "So you live with your mum then?"

"No she died a long time ago, I live with my Uncle instead," she said, "And you?"

"My Gran, Augusta Longbottom." Just the name seemed to make Neville nervous.

Hermione was back again as a voice echoed through the train, "We will be reaching Hogwarts in five minutes time. Please leave your luggage on the train, it will be taken to the school separately."

Cassie was glad that she wasn't the only nervous one as Neville's face paled and Hermione began to babble a stream of facts quoted from _Hogwarts: A History._

The train slowed right down and finally stopped. People pushed their way towards the door and out on to a tiny, dark platform. The three of them looked around in confusion. Then a lamp came bobbing over the heads of the students and all three of them looked up at a man with bright beetle black eyes and a tangle of hair with a long shaggy beard.

"C'mon, follow me- any more firs' years? Mind yer step, now! Firs' years follow me!"

Slipping and stumbling, they followed the huge man down what seemed to be a steep, narrow path. It was so dark either side of them that there must be thick trees there.

"Yeh'll get yer firs' sight o' Hogwarts in a sec," he called over his shoulder, "jus' round this bend here."

There was a loud "Oooooh!"

The narrow path had suddenly opened on to a great black lake. Perched atop a high mountain on the other side, it's windows sparkling in the starry sky, was a vast castle with many turrets and towers.

"No more'n four to a boat!" He called, pointing to a fleet of little boats sitting in the water by the shore. They saw Harry and Ron get into one to be joined by two more boys. Cassie, Neville and Hermione sat in the small empty boat to its left.

"Everyone in?" he shouted. "Right then- FORWARD!"

And the fleet of little boats moved off all at once, gliding across the lake, which was as smooth as glass. Everyone was silent, staring up at the great castle overhead. It towered over them as they sailed nearer to the cliff on which it stood.

"Heads down!" the shaggy haired man yelled as the first boats reached the cliff; they all bent their heads and the little boats carried them through a curtain of ivy which hid a wide opening in the cliff face.

They were carried along a dark tunnel, which seemed to be taking them right underneath the castle, until they reached a kind of underground harbour, where they clambered out on to the rocks and pebbles.

"Oy, you there! Is this your toad?" the big man asked, who was checking the boats as people climbed out of them.

"Trevor!" cried Neville blissfully, holding out his hands. Then they clambered up a passageway in the rock after the man, coming out at last on to smooth, damp grass right in the shadow of the castle.

They walked up a flight of stone steps and crowded around the huge, oak front door.

"Everyone here? You there, still got yer toad?"

He raised a gigantic fist and knocked three times on the castle door.


	2. Chapter 2

**Disclaimer: I do not own the world or character's of Harry Potter.**

**Author's note: Enjoy! **

The door swung open at once. A tall, black-haired witch in emerald-green robes stood there. She had a very stern face and Cassie's first thought was that this was not someone to cross, she doubted from her piercing eyes that this Professor would tolerate any trickery in her classes.

"The firs' years, Professor McGonagall," the shaggy haired man said and Cassie suddenly remembered Remus telling her about the Gryffindor's formidable Head of House.

"Thank you, Hagrid. I will take them from here."

She pulled the door wide. The Entrance Hall was so big you could have fitted Remus' house in it twice. The stone walls were lit with flaming torches, the ceiling was too high to make out, and a magnificent marble staircase facing them led to the upper floors.

They followed Professor McGonagall across the flagged stone floor and showed the first years into a small empty chamber off the hall. They crowded in standing rather closer together than they would usually have done, peering about nervously.

"Welcome to Hogwarts," said Professor McGonagall. "The start-of-term banquet will begin shortly, but before you take your seats in the Great Hall, you will be sorted into your houses. The sorting is a very important ceremony because, while you are here, your house will be something like your family in Hogwarts. You will have classes with the rest of your house, sleep in your house dormitory and spend free time in your house common room.

"The four houses are called Gryffindor, Hufflepuff, Ravenclaw and Slytherin. Each house has its own noble history and each has produced outstanding witches and wizards. While you are at Hogwarts your triumphs will earn your house points, while any rule-breaking will lose house points. At the end of the year, the house with the most points is awarded the House Cup, a great honour. I hope each of you will be a credit to whichever house becomes yours.

"The Sorting Ceremony will take place in a few minutes in front of the rest of the school. I suggest you all smarten yourselves up as much as you can while you are waiting."

Her eyes lingered for a moment on Neville's cloak which was fastened under his left ear, and on Ron's smudged nose.

"I shall return when we are ready for you," said Professor McGonagall. "Please wait quietly."

She left the chamber.

Cassie's nerves returned in force. The sorting ceremony was going to happen very soon and then people would know. They would know her name and never trust her. What house could possibly want her? There wasn't a chance she'd ever qualify for the loyal Hufflepuffs and the smart Ravenclaws, her inner troublemaker wouldn't allow it, which just left Gryffindor, the house her father betrayed or Slytherin the house of Deatheaters, liars and cheats. It was difficult to judge, people would expect her to be a Slytherin like most of her ancestors and she could fit in there, but it wasn't where she wanted to be. The people she'd met on the train had convinced her of that. She wanted to be in the same house as the troublemaking twins, as Neville Longbottom, who she was sure would be a Gryffindor, the bossy muggle-born Hermione Granger and particularly Harry Potter. She wanted to know him like her father and uncle knew James Potter (minus the epic betrayal part at the end). To be in any other house didn't feel like an option, she was not her father and she would prove it to them.

Cassie was taken aback by several people's screams.

About twenty ghosts had just streamed through the back wall. Pearly-white and slightly transparent, they glided across the room talking to each other and hardly glancing at the first-years. They seemed to be arguing. She recognised what looked like a fat little monk as the Fat Friar from her Uncle's descriptions. "Forgive and forget, I say. We ought to give him a second chance-"

"My dear Friar, haven't we given Peeves all the chances he deserves? He gives us all a bad name and, you know, he's not really even a ghost- I say, what are you all doing here?"

A ghost wearing a ruff and tights had suddenly noticed the first years.

Nobody answered.

"New students!" said the Fat Friar, smiling around at them. "About to be sorted, I suppose?"

A few people nodded mutely.

"Hope to see you in Hufflepuff!" said the Friar. "My old house, you know."

"Move along now," said a sharp voice. "The Sorting Ceremony's about to start."

Professor McGonagall had returned. One by one, the ghosts floated away through the opposite wall.

The tense knot in her stomach tightened. Feeling slightly numb, she got into line behind Ron, with Hermione and Neville behind her, and they walked out of the chamber, back across the hall and through a pair of double doors into the Great Hall.

Remus' descriptions had not done it justice. There were thousands of candles which floated in mid-air over the four long house tables, where rest of the students were sitting. At the top of the Hall was another long table where the Professors sat behind it. Professor McGonagall led the first years up here, so that they came to a halt in a line facing the other students. The hundreds of faces staring at them looked like pale lanterns in the flickering candlelight. Dotted here and there among the students, the ghosts shine misty silver. Cassie found some comfort in Hermione's whispered quotations. "It's bewitched to look like the sky outside, I read about it in _Hogwarts: A History"_

It was hard to believe there was a ceiling there at all, and that the Great Hall didn't simply open on to the heavens.

Professor McGonagall silently placed a four-legged stool in front of the first-years. On top of the stool she put the pointed Sorting hat. For a few seconds, there was complete silence. Then the hat twitched. A rip near the brim opened wide like a mouth – and the hat began to sing:

'_Oh, you may not think I'm pretty,_

_But don't judge on what you see,_

_I'll eat myself if you can find_

_A smarter hat than me._

_You can keep your bowlers black,_

_Your top hats sleek and tall,_

_For I'm the Hogwarts Sorting Hat_

_And I can cap them all._

_There's nothing hidden in your head_

_The Sorting Hat can't see,_

_So try me on and I will tell you_

_Where you ought to be._

_You might belong in Gryffindor,_

_Where dwell the brave at heart,_

_Their daring, nerve and chivalry_

_Set Gryffindors apart;_

_You might belong in Hufflepuff,_

_Where they are just and loyal,_

_Those patient Hufflepuffs are true_

_And unafraid of toil;_

_Or yet in wise Ravenclaw,_

_If you've a ready mind,_

_Where those of wit and learning,_

_Will always find their kind;_

_Or perhaps in Slytherin_

_You'll make your real friends,_

_Those cunning folk use any means_

_To achieve their ends._

_So put me on! Don't be afraid!_

_And don't get in a flap!_

_You're in safe hands (though I have none)_

_For I'm a Thinking Cap!'_

The whole hall burst into applause as the hat finished its song. It bowed to each of the four tables and then became quite still again.

"So we've just got to try on a hat!" Ron whispered to Harry. "I'll kill Fred, he was going on about wrestling a troll."

Cassie was too nervous to laugh.

Professor McGonagall now stepped forwards holding a long roll of parchment.

"When I call your name, you will put on the hat and sit on the stool to be sorted," she said. "Abbott, Hannah!"

A pink-faced girl with blonde pigtails stumbled out of line, put on the hat which fell right down over her eyes, and sat down. A moment's pause-

"HUFFLEPUFF!" shouted the hat.

The table on the right cheered and clapped as Hannah went to sit down at the Hufflepuff table.

"Black, Cassiopeia!" Professor McGonagall's eyes went wide in surprise and she turned to the line of first years to watch for her. Hermione gave her hand a light squeeze as she stepped up to the stool amid the murmurs and whispers of the other students. Cassie breathed a sigh of relief as the hat covered her eyes, blocking out the pale faces staring up at her.

"Ah well, well, well. A young Black eh? Plenty of cunning I see and the bravery of your father too. My, my, aren't you a tricky one. No particular preference my dear? Ah yes, Slytherin would be the easiest of paths for you but what's life without a few challenges, I think- GRYFFINDOR!"

There was smattering of applause that was soon hushed, but was taken up by some enthusiastic first years behind her. Cassie flashed them a grateful smile before hurrying over to the table where the twins were exchanging dumbstruck looks.

Immediately after taking a spare seat as far from the older student's as she could get, she turned back to the Sorting, focusing on it intently without really taking it in. Her heart was still pounding.

At least she'd partway become Neville, Hermione and Harry's friend. She knew it wasn't likely to last but hopefully they could look past her family name.

She applauded with all of the others when "Brown, Lavender," became the second first-year to join Gryffindor, followed soon after by "Finnigan, Seamus."

"Granger, Hermione!"

Hermione almost ran to the stool and jammed the hat eagerly on to her head.

"GRYFFINDOR!" shouted the hat. Cassie cheered and Hermione almost ran over to join her. On Hermione's other side another, older Weasley boy stuck out his hand and shook hers. The glittering prefect badge on his chest puffed out proudly.

When Neville Longbottom was called, he fell over on his way to the stool. The hat took a long time to decide with Neville. When it finally shouted "GRYFFINDOR," Neville ran off still wearing it, and had to jog back amid gales of laughter to give it to "Macdougal, Morag."

Neville took a seat opposite them, next to Seamus.

"I think that moment makes it into the top ten most embarrassing moments of my life." Neville grimaced, leaning slightly over the table to talk to the two girls better.

Cassie laughed good naturedly, the knot in her stomach had loosened, the decision was made, she was a Gryffindor. "What number did this moment make?"

"Ssh!" Hermione hissed, intently watching the sorting.

Neville solemnly held up four fingers before cracking out a shy grin, making Cassie struggle to hold on to her laughter.

"Potter, Harry," made them at last turn their attention back to the sorting.

As Harry stepped forward, whispers suddenly broke out like hissing fires all over the hall.

"Potter, did she say?"

"_The_ Harry Potter?"

People were craning to get a better look at him as the hat dropped onto his head. It took a full minute for the hat to finally decide on "GRYFFINDOR!" and the relief on his face was evident as he was given the loudest cheer yet. Percy the Prefect got up and shook his hand vigorously, while the Weasley twins yelled, "We got Potter! We got Potter!"

And now there was only three people left to be sorted. "Turpin, Lisa," became a Ravenclaw and then it was Ron's turn. He was pale green by now, a second later the hat had shouted, "GRYFFINDOR!"

Cassie settled on a brief, polite clap rather than the enthusiastic cheering she had given for Harry. Ron collapsed into the seat next to him.

"Well done, Ron, excellent," said Percy Weasley pompously across them as "Zabini, Blaise" was made a Slytherin. Professor McGonagall rolled up her scroll and took the Sorting hat away.

Albus Dumbledore then got to his feet , his eyes twinkling behind his half-moon spectacles. He was beaming at the students, his arms opened wide, as if nothing could have pleased him more than to see them all there.

"Welcome!" he said. "Welcome to a new year at Hogwarts! Before we begin our banquet, I would like to say a few words. And here they are. Nitwit! Blubber! Oddment! Tweak!

"Thank you!"

He sat back down. Everyone clapped and cheered.

"Is he- a bit mad?" Harry asked Percy uncertainly.

"Mad?" said Percy airily. "He's a genius! Best wizard in the world! But he is a bit mad yes. Potatoes, Harry?"

The feast spread out before them was of a size and magnitude Cassie had never seen. In fact it was more food than she felt she'd ever seen and it all looked mouth-watering. She had some of everything, even a couple of mint humbugs, although she couldn't figure out what those muggle sweets were there for.

She watched as the twins' friend Lee Jordan levitated his 'pet' tarantula over to the Hufflepuff table, landing in front of a second year who promptly screamed quite girlishly.

Then Professor McGonagall was there, her lips a thin line of exasperation.

"Mr Jordan, detention! And I'll be holding onto your pet until then."

The twins high-fived Lee as the Professor stalked away. "And the award for the first detention of the year goes to Lee Jordan!" The twins cheered happily.

Cassie snorted into her pumpkin juice, making Neville and Hermione look at her strangely.

"What was that about?" Neville frowned.

At the look of disapproval Hermione shot at the twins Cassie mouthed "later" to Neville and swallowed another gulp of pumpkin juice.

When everyone had eaten as much as they could, the remains of the food disappeared and Professor Dumbledore called for attention again.

"Ahem- just a few more words now we are all fed and watered. I have a few start-of-term notices to give you.

"First-years should note that the forest in the grounds is forbidden to all pupils. And a few of our older students would do well to remember that as well."

Dumbledore's twinkling eyes flashed in the direction of the Weasley twins.

"I have also been asked by Mr Filch, the caretaker, to remind you all that no magic should be used between classes in the corridors.

"Quidditch trials will be held in the second week of term. Anyone interested in playing for their house teams should contact Madam Hooch.

"And finally, I must tell you that this year, the third-floor corridor on the right-hand side is out of bounds to everyone who does not wish to die a very painful death."

There was a smattering of laughter throughout the hall. Cassie was intrigued. What could they possibly have put in a school full of children that was so dangerous? Why would they have put anything there?

"And now, before we go to bed, let us sing the school song!" cried Dumbledore.

He gave his wand a little flick as if he was trying to get a fly off the end and a long golden ribbon flew out of it, which rose high above the tables and twisted itself snake-like into words.

"Everyone pick their favourite tune," said Dumbledore, "And off we go!"

And the school bellowed:

_'Hogwarts, Hogwarts, Hoggy Warty Hogwarts,_

_ Teach us something please,_

_ Whether we be old and bald_

_ Or young with scabby knees,_

_ Our heads could do with filling_

_ With some interesting stuff,_

_ For now they're bare and full of air,_

_ Dead flies an bits of fluff,_

_ So teach us things worth knowing,_

_ Bring back what we've forgot,_

_ Just do your best, we'll do the rest,_

_ And learn until our brains all rot."_

Everybody finished the song at different times. At last, only the Weasley twins were left singing along to a very slow funeral march. Dumbledore conducted their last few lines with his wand, and when they had finished, he was one of those who clapped the loudest.

"Ah, music," he said, wiping his eyes. "A magic beyond all we do here! And now, bedtime. Off you trot!"

The Gryffindor first-years followed Percy through the chattering crowds, out of the Great Hall and up the marble staircase. Cassie stifled a yawn, as she gazed about in wonderment. The people in the portraits whispered and pointed as they passed and Cassie watched them in awe. Uncle Remus and herself lived a lot in the muggle world so she wasn't used to seeing so many moving portraits. And the castle itself was a moving labyrinth of staircases and vanishing doors, sliding panels and hidden rooms. She could barely contain her excitement at getting to explore the halls of Hogwarts and find out all of its secrets.

Her toe caught on the edge of a step and she almost fell through a missing stair. Percy caught her arm just before she slipped through the gap. "Mind your step, they often vanish."

Behind her, Neville gulped and clung to the railing as he leapt past her. She was so busy watching her feet from then on that she completely missed the whole exchange with Peeves.

As Percy told the Fat Lady portrait the password, "_Caput Draconis,"_ they all scrambled in and found themselves in the Gryffindor common room, a cosy, round room full of squashy armchairs.

Percy directed the girls through one door to their dormitory, it led to a spiral staircase and at the very top they found their beds at last. Their school trunks already laid at the base of the bed, all Cassie could bring herself to do was scribble out a quick note to Remus, promising herself that she'd send it in the morning.

_To Remy,_

_GRYFFINDOR! I'M IN GRYFFINDOR! You were right. _

_From the one and only,_

_Cass X_


	3. Chapter 3

**Disclaimer: I think you get the idea but, I do not own the world of Harry Potter and his friends.**

**Author's note: I had so much fun writing this chapter! Please enjoy!**

_Dear Cassie,_

_I knew it! Congratulations on getting in to Gryffindor. Write soon and tell me about your friends and your classes. Say hello to Professor McGonagall from me and __**try**__ to stay out of trouble._

_From,_

_Remus_

"We're lost," Neville stated frankly.

"We are not lost! This is a shortcut, I swear!" Hermione and Neville exchanged sceptical looks. Cassie could see why they were doubtful. They'd left the Great Hall over twenty minutes ago and were still in search of the correct staircase down to the dungeons. It was also not the first time in the past week that Cassie had led them on a wild goose chase down the corridors of Hogwarts. It was only yesterday that they were on their way to transfiguration when she'd led them through a shortcut behind a statue of a gargoyle, which was actually a hidden entrance to the charms classroom. Needless to say, Professor Flitwick was extremely surprised when they stumbled out of his store cupboard.

"Look. There's an older student. Why don't we just ask for directions?" Hermione said simply.

Cassie gave her a doubtful look.

"What? It's a reasonable suggestion. And if you're too chicken…"

Neville interrupted. "What do chickens have to do with this?"

There was a pause.

"I am not too chicken! Besides we're not lost, the dungeons are just down the staircase behind the tapestry of the lady in a blue nightgown," Cassie frowned. "Or was that the way to the Slytherin Common room? Wait no, that's behind a painting of a knight on horseback. So is this the one behind the one of the fruit bowl…"

Hermione groaned, "and you're still saying we're not lost?"

Cassie nodded, an expression of deep thought on her face.

"That's it, I'm asking that student." Hermione was just about to shout out to the older student when Cassie grabbed her arm and pointed to a tapestry of the night sky.

"Found it!" She cried, dragging the other two along behind her.

Hermione sighed as the tapestry was roughly pushed aside to reveal a dark staircase. "I still say we'd be better off asking, just to double check!"

"_Lumos," _Cassie murmured and her wand tip lit up, highlighting her incredulous face. "You mean to say that, asking a _Slytherin_, who I just so happen to know is also a Fourth year called Marcus Flint, we'd have gotten to Potions class faster?"

Hermione gave a curt nod.

"You are delusional. Slytherins and Gryffindors do _not_ help each other. We'd have ended up the other side of the castle if we'd listened to him. Slytherins take joy in torturing ickle firsty Gryffindors."

Hermione huffed, lit her wand angrily and marched down the staircase.

"You know she hates being wrong," Neville accused.

Cassie shrugged it off and called back over her shoulder. "At least she's stopped nagging though."

It was the end of their first week at Hogwarts, Friday morning and they were on their way to Potions class, a subject that Cassie was a mixture of eager and anxious about. Remus had explained that her father and James Potter had not gotten along well at all with Professor Snape so she wasn't expecting a warm greeting, but she was quite fascinated with the subject. Potions were the only lesson she could practice over the Summer holidays without getting a warning letter from the Ministry of Magic. Also potions were great for pranks.

They made it to the dank dark basement room, just in time for the start of the lessons. As they took their seats Severus Snape strode into the classroom, his robes twirling about him like bat's wings.

He began the roll call and, like most of the teachers had throughout the week, paused after he spoke her name. "Black, Cassiopeia." He gave her a chilling sneer, to which she stared back at him defiantly.

Although his reaction to her was nothing compared to "Potter, Harry." Snape's frosty gaze could have turned him into a block of ice.

She did her best to tune out the professor's 'Welcome' speech but found it too difficult to ignore the deep voice.

"You are here to learn the subtle science and exact art of potion making," he began. He spoke barely more than a whisper, but they caught every word – like Professor McGonagall, Snape had a gift of keeping a class silent without effort. "As there is little foolish wand-waving here, many of you will hardly believe this is magic. I don't expect you will understand the beauty of the softly simmering cauldron with its shimmering fumes, the delicate power of liquids that creep through human veins, bewitching the mind, ensnaring the senses… I can teach you how to bottle fame, brew glory, even stopper death – if you aren't as big a bunch of dunderheads as I usually have to teach."

"Potter!" said Snape suddenly. "What would I get if I added powdered root of asphodel to an infusion of wormwood?"

Harry's head shot up from his hastily scribbled notes. His face was white and he looked like a deer caught in headlights. Hermione's hand shot into the air.

"I don't know, sir,' said Harry.

"Tut, tut – fame clearly isn't everything."

"Greasy git," Cassie muttered under her breath. Dean Thomas sniggered beside her. Snape's eyes snapped up and focused on her.

"Let's try again. Black, where would you look if I told you to find me a bezoar?" Cassie suddenly found herself unable to hold her tongue. Usually she could quell her sarcastic comments but the satisfied gleam in Snape's eye egged her on.

"Well I'd look in your cupboard, Professor." A couple of other Gryffindor's bravely hid their sniggers.

Snape's eyes narrowed. "A point from Gryffindor house for your cheek, Black." He turned his attention back to Harry.

"What is the difference, Potter, between monkshood and wolfsbane?"

Hermione's hand was waving about frantically. Surprisingly enough Cassie actually did know the answer to this one as it was a common ingredient in Remus' Wolfsbane potion. When they could afford the ingredient (which wasn't often) he would pay a potions master to make him a batch. Monkshood and wolfsbane is the same thing.

"I don't know," Harry said quietly. "I think Hermione does, though, why don't you try her?" Several people in the room laughed.

"Another point from Gryffindor!" Snape snapped. He flashed a fierce look at Hermione. "Sit down!"

Things did not improve for the gryffindors throughout the lesson. They were asked to create a simple cure for boils. Which thanks to Remus' tutoring was made with ingredients Cassie had practice in preparing and with Dean's help they managed to make a fairly average looking potion. However when Snape inspected the contents of their cauldron he told them that the consistency was all wrong and vanished it from their sight to do again.

As Cassie moved over to the potions cudboard, grumbling about how unfair Snape was, she spotted Draco Malfoy stood with a handful of porcupine quills over Neville and Seamus's cauldron whilst their backs were turned. Before she could call out and stop him, the quills were dropped into the grey potion, turning it an acidic green and erupting into a hissing green cloud of smoke. The cauldron bubbled and melted as if it were made of chocolate. Unfortunately Draco had scampered out of range and back to his partner, whilst poor Neville was hit in the face with the broiling liquid as he turned at the wrong moment. The liquid oozed across the floor and began to eat at people's shoes. Soon everyone was standing on their stools out of range of the liquid. Cassie had leapt onto the raised part of the classroom where Snape's desk stood, narrowly avoiding the corrosive acid.

Neville moaned in pain as angry boils appeared all over his arms and legs.

"Idiot boy!" snarled Snape, clearing the spilled potion away with one wave of his wand. "I suppose you added the porcupine quills before taking the cauldron off the fire?"

Neville whimpered as boils started to pop up all over his nose.

"Take him up to the hospital wing,' Snape spat at Seamus. Then he rounded on Harry and Ron, who had been working next to Neville.

"You – Potter – why didn't you tell him not to add the quills? Another point from Gryffindor!"

Draco Malfoy's smug look was enough to drive Cassie over the edge. Clearly Professor Snape wouldn't punish his prized student, he'd bragged about Malfoy's potion only moments before the incident. But Cassie would get revenge for Neville. The lesson finally ended ten minutes later, Dean and Cassie hadn't managed to complete their second attempt at the potion so Snape had given them an extra two inches of homework on the importance of quality control in brewing boils antidote.

As they left the classroom Cassie shuffled over to the Slytherin side of the room and made sure she filed out just behind Malfoy. She quickly removed her wand from her robes and whispered the incantation for the stinging jinx. Remus had mentioned it once in a story and from her reading of the defence against the dark arts text she had figured out the incantation. Very slowly, Draco Malfoy's hands began to swell. Cassie stuffed her wand away and then quickly ran after the other Gryffindor's who were just moving out of sight. Just as she turned the corner she got a glimpse of Draco Malfoy's face puckering up, his face becoming a distorted mess. She laughed as she caught up with Dean.

"What're you laughing at?" He gave her a quizzical look.

Cassie grinned and pulled him up to where Ron and Harry were walking. "Come with me to visit Neville and you will see something hilarious."

Harry shrugged, "Anything to cheer me up after that lesson."

The boys followed her, part out of curiosity but mostly to see how Neville was.

As they arrived at the Hospital wing and approached Neville's bed, they could see he was looking much better. His face had returned to its normal size and Seamus was cheering him up with some chocolate ice mice. Neville looked up at them in surprise.

"What're you doing here?" he asked.

"We came to see how you are," Ron said pinching an ice mouse from his lap.

"Yeah, and Cass promised us we'd see something hilarious. Well we're waiting," Dean crossed his arms expectantly.

Unable to stop herself she giggled at the thought of what she'd done, but thinking they might be cross she'd done it unjustly, she explained herself.

"Well, Neville didn't make a mistake with that potion." The others looked at her interestedly. She explained what she'd seen Draco do. Ron went bright red in anger and Seamus looked like he was going to punch someone.

"I have half a mind to curse him right now!" Ron exclaimed loudly causing Madam Pomfrey to shush them from her perch by another patient.

At that moment the door was pushed open by Crabbe and Goyle as they dragged an unrecognisable Draco Malfoy into the room behind them.

"You're too late," Cassie said with a satisfied grin.

"Is that-?"

"No way is that -!"

"You cursed Draco Malfoy!" Seamus finally stammered out what the others couldn't. Draco Malfoy's face had ballooned to twice its regular size, his fingers were the size of sausages and his robes were stretched tight across his body.

Madam Pomfrey bustled over as if she'd seen the same thing a hundred times before and ushered Malfoy over to a curtained off section of the Hospital Wing. As soon as Draco Malfoy was out of sight the Gryffindors erupted into hysterical laughter.

"Way to go Cass," Harry smirked as they made their way to lunch, "definitely made my day!"

_Dear Remus,_

_Classes are ok, nothing much is happening in them yet. It's all been theory so far, though that hasn't stopped them giving us masses of homework. You were right, Snape doesn't like us. Me and Harry that is, though he's giving Neville a tough time too. He made Dean and I remake our potion just because it was a little too lumpy! Then we got extra homework for not completing it the second time around! I really hate Snape! Plus Draco Malfoy is being a real tosspot lately, he ruined Neville's potion on purpose, putting him in the hospital wing. Don't worry, I got him back for that trick._

_Flying lessons start soon, hope I get a good broom. The announcement was on the noticeboard when we got back from lessons today. _

_I'd better get this homework done if I don't want Hermione nagging me all weekend, plus I want to explore the castle some more. I wish I had a muggle pen; these quills are driving me mad! And why doesn't parchment come lined? _

_By the way which way was the shortcut to potions? We may or may not have gotten lost..._

_From the magnificent,_

_Cassie x_


End file.
